Originally Posted by Funk

There are some sim instructors that commute. They kind of bid for which periods they want to instruct, but it isn’t as robust as bidding on the line, so you’ll sometimes have very senior sim instructors working sim periods that weren’t anywhere near what they had wanted to do. So, commutability is more correctly described as, “it depends.” YMMV

As for progression, that depends entirely on the rest of your resume and application, but I’ve never heard of a separate pathway to guarantee a job or interview. If you are an SLI (seniority list instructor), you are paid 85 hrs guarantee at the highest rate you can hold for the seat you’re in. For example, you can instruct the 717 right seat, but if there is one pilot junior to you on the 777, then you get paid 777 FO pay. I have no idea what the pay is for a contract instructor.